With Samsung’s mobile Gear VR headset hitting stores in time for the holidays, a deluge of new VR users is on the way. If you’re among them, here’s three quick warnings you should heed.

1. Never Leave Your Gear VR Face Down or Outside

As a mobile VR headset, Gear VR is easily portable and may find itself resting on the coffee table of a living room, taken to a friend’s house, or even used outside on the patio. In any case, never leave your Gear VR headset face down (lenses up) or outside. If the sun catches the lenses at the wrong angle it can focus the rays onto your phone screen like a magnifying glass, possibly ruining the screen of your precious (and expensive!) phone.

This issue affects other headsets as well. At least one Oculus Rift user accidentally fried their device and shared the warning:

There is now a burn mark in the center of my left part of the screen from where the sunlight was focused into a small fire. I hope this save’s someone else from making the same mistake.

The face down position is especially prominent when using the Gear VR without any straps attached (like a View-Master), so be extra careful when passing it around that someone doesn’t inadvertently rest it face down, putting it in a vulnerable position as the sun sweeps across the sky and its rays across the room.

2. Never Use Gear VR Without a Phone Docked in the Headset

Gear VR is compatible with a number of different phones (depending upon which headset you have). Without a phone locked into the headset, the lenses, which normally focus light from the display into your eye, are exposed. If you are wearing the headset with no phone and accidentally look at a powerful light you can risk damaging your vision as the rays from that light will be focused into your eye. NEVER look at the sun through the bare headset.

3. Gear VR Should Not Be Used by Anyone Younger than 13

Samsung and Oculus’ official stance is that Gear VR should not be used by anyone less than 13 years old. The Gear VR manual reads:

The Gear VR should not be used by children under the age of 13. Watching videos or playing games with the Gear VR may affect the visual development of children.

Although Gear VR is fun and accessible, it may be best to play it safe even if the youngsters are begging for a try. For those older than 13, Samsung still urges caution for extended use:

When children, age 13 or older, use the Gear VR, adults should limit their usage time and ensure they take frequent breaks. Adults should monitor children closely after using the Gear VR if children feel discomfort.